A tool holder is one of the machining components that is attached to a machine and has a clamp on the other side to hold the tool in place firmly to perform the machining process. The performance of the tool holder can affect the accuracy of the machine tool and also the product quality. The right tool holder provides a safe connection between the machine and high-speed tools. Since the tool holder is involved in a high precision mechanization process, the cutting tool is often required to reach very high RPMs, it is very important to have a quality tool holder with high gripping force, level of accuracy, and balance. If there is any imbalance occurred between the machine and high-speed tool, it may damage the product or result in undesired finishing. This could even wear down the spindle and shorten the lifespan of the machine. In this case, you should choose a suitable tool holder and install it properly to ensure the machining process is performed safely and accurately.
Generally, all the tool holders include three unique parts, which are the flange, the tapes, and the collet pocket. The taper is designed in a corn shape that connects to the spindle when changing the tools. The flange is located at the middle portion of the tool holder and is attached to the tool changer that is being moved in relation to the spindle. The collet pocket is where the insert of the collet is secured.
There is a wide range of tool holders available for different industries and industrial purposes ranging from farm implements to medical equipment. It is important to understand the tool holders before choosing the right tool holders for your machinery and applications. The choice of the tool holder is largely depending on the type of machine, the product, and the process. A long tool holder is able to meet depth requirements when there is a need for insertion into the machine, while a short tool holder is also preferred in some applications as it reduces the risk of imbalance which may lead to damages and vibration during the process. You also need to consider other factors when selecting the type of tool holder. For example, whether you need a quick tool change or what is the desired cutting finishing and size is.
Common Types of Tool Holders
Shrink fit tool holders
Shrink fit holders use heating and cooling to employ clamping force to the tool. They have a very exact and firm fit that is preferred to be used in high precision manufacturing or high rpm applications. They don’t have moving parts and are able to provide the best balance during the process. Shrink fit holders have the smallest nose diameter when compared to other types of tool holders. The price of shrink fit tool holders is relatively high but it is value for money since they provide high specifications and many advantages. Although the tool changing can be done quickly, it may take time for the holder to cool down and since the holder gets very hot during the expansion step, proper care must be taken to avoid damages or burns.
Collet chucks
Collet chucks are one of the most versatile types of tool holders. They can grab any size of the shank by switching the collects and as long as the shank size is within the range of collet. They are usually used for holding different machinery toolings such as drills, end mills, counter sinks, taps, center drills, and many other tools. Collect chucks provide a strong grip that is suitable for medium roughing applications. They are available in many gauge lengths from short to very long. However, collet chucks required a long tool changing time as small chips will be build up inside of the collet, the collet and collet nut should be disassembled each time when you inserting a new tool for cleaning.
End mill holders
End mill holders are mainly for milling operation and keeping milling tools in place. They have a small nose diameter and are available in a wide range of gauge lengths from short to long. End mill holders are simple, rigid, great for heavy roughing, and have a quick tool changeover time. But, they can only hold one shank size and the tool will not be on the center if the shank is undersized. In addition, the shank also must have a flat for setting the screw to lock on it. After the set screw is clamped on the shank flat, it can offer a great grip with little chance of slippage.
Drill Chuck Holders
Drill chuck holders offer a quick tool change, no collets are needed, and can hold any size of shank within the specific range. But they offer a low gripping force and the diameter of the nose tends to be bigger than other types of tool holders. Drill chuck holders are suitable for holding drills for light application. It is unable to hold end mills or to handle side loads.
Hydraulic Chuck Holders
As per their name stated, hydraulic chuck holders use fluid to compress the internal membrane inside the holder. They give a uniform pressure around the cutting tool. Hydraulic chuck holders are suitable to be used for machining processes that need high accuracy such as end mill, drills, reamers, grinding tools, etc. They are popular in the aerospace, automotive, and medical industries as they can deliver great grip and concentricity. Hydraulic chuck holders have a fairly slim nose design which is slightly bigger than shrink fit tool holders. They can offer the quickest tool change among all types of tool holders. However, their prices are expensive and only can handle one size shank without the adaptive sleeve.
MecHero Malaysia provides a variety of tool holders and hardware that meet your requirement. You can always contact us at +6011-7000 7687 or email us at my.mechero@gmail.com for an inquiry about machining tool holders in Malaysia. As a steel and online hardware store in Malaysia, we also supply a wide range of steel materials, general hardware, or mechanical components. Tell us your requirements now and we can advise you accordingly.
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